Guess my Number

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Problem Generate a program where the computer chooses a random number between 1 and 10 and the user is continuously asked to guess it until they are correct. Use the following guidelines in coming up with a solution: Scanner to use for input Math.random() for generating the random number While loop for continuously asking for a guess until right Boolean variable for indicating when the while loop is done		While and For Loops
Solution To begin you need to get references for Math.random and Scanner import javax.swing.*; import java.lang.Math; import java.util.Scanner; You're going to need 4 variables to use for this problem int randNum; //store the random number to be guess Scanner input = new Scanner(System.in) //this will get the guess of the user int guess; //store the guess of the user Boolean correct = false; //this will serve as loop condition until user get the right answer To generate a random number between 1 and 10 we will need to use the following code. //(int)(Math.random() * 10 generates a random number from 0 to 9 //to get a random number from 1 to 10 we need to add 1 randNum = (int)(Math.random() * 10) + 1; Use the Scanner to get the input of the user. using the method hasNextInt() will check if the user entered a valid number. System.out.print("Enter a guess between 1 and 10: "); //get the guess from the user if(input.hasNextInt()) //ensure that the user entered a number { guess = input.nextInt(); //will stored the number entered by the user if(guess == randNum) // to compare if the guessed number is equal to the generated number from Math.random() { correct = true; //set correct to true if its equal System.out.println("You are correct"); } else { System.out.println("You are incorrect"); } } else //program will enter this if entered input was not a number { System.out.println("Numbers Only"); input.next(); } Enter a guess between 1 and 10: 3 You are incorrect Enter a guess between 1 and 10: a Numbers Only Enter a guess between 1 and 10: 1 You are correct Since you do not know when to stop the loop, While Loop is necessary for this. Use the boolean you created to know if the loop needs to stop, in this case if the user guessed the number. //loop until correct changes to true while(correct == false) { //codes } For the final solution code you can look under the code heading.
Code Solution Code import java.lang.Math; //needed for Math.random import java.util.Scanner; public class GuessMyNumber { public static void main(String [ ] args) { int randNum; //used to store the randNum we generate Scanner input = new Scanner(System.in); //used to get the guess int guess = 0; //use to store the guess boolean correct = false; //loop variable initialized to false meaning our guess is incorrect //(int)(Math.random() * 10 generates a random number from 0 to 9 //to get a random number from 1 to 10 we need to add 1 randNum = (int)(Math.random() * 10) + 1; while(correct == false) { //get the guess from the user System.out.print("Enter a guess between 1 and 10: "); //get the guess from the user if(input.hasNextInt()) //ensure that the user entered a number { guess = input.nextInt(); //will stored the number entered by the user if(guess == randNum) // to compare if the guessed number is equal to the generated number from Math.random() { correct = true; //set correct to true if its equal System.out.println("You are correct"); } else { System.out.println("You are incorrect"); } }//if else //program will enter this if entered input was not a number { System.out.println("Numbers Only"); input.next(); }//else }//while }//main }

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